Esophageal atresia is a serious birth defect in which the esophagus, the long tube connecting the mouth to the stomach, is segmented and does not form a continuous passageway into the stomach. In particular, infants suffering from esophageal atresia are born with separate upper and lower esophageal portions (commonly referred to as esophageal sacs). In most forms of esophageal atresia the upper esophageal sac begins to fill with mucus and saliva shortly after birth. Consequently, excessive drooling, choking, and coughing are symptomatic of esophageal atresia. Moreover, an infant afflicted with this disorder instantaneously returns (i.e., expels) what he or she is fed, thereby preventing the digestion and absorption of orally administered foods.
There are several types of esophageal atresia. In one type of esophageal atresia, the upper and lower esophageal sacs are not attached to the trachea. That is, the lower esophageal sac does not develop an esophagotracheal fistula. In another type of esophageal atresia, the upper esophageal portion ends as a blind sac, whereas the lower esophageal portion is connected to the trachea by a narrow canal at a point just above the tracheal bifurcation. In yet another type of esophageal atresia, the narrow canal between the trachea and the distal portion of the esophagus forms a ligamentous cord. In rare instances, both the proximal and distal portions of the esophagus actually open into the trachea.
For a period of about three months after birth, the esophageal sacs spontaneously undergo a period of rapid growth toward each other. A number of different techniques have been used during this spontaneous growth period to achieve a more rapid approximation of the esophageal sacs. These techniques have included, for example, the use of a large external electromagnet, surgical techniques, and internally positioned magnets.
One such technique is described in detail in U.S. Pat. No. 3,986,493 (hereinafter “the '493 patent”), titled “Electromagnetic Bougienage Method” uses an external annular electromagnet to intermittently magnetize bougies located within each esophageal sac to lengthen the esophageal sacs and eventually surgically join the esophageal sacs.
Yet another method of treating esophageal atresia involves surgically applying sutures to the opposing ends of the esophageal sacs. The sutures create traction forces to the ends of the esophageal sacs during the rapid growth period, thereby causing further elongation of the esophageal sacs. Ultimately, the sutures cause the esophageal sacs to grow together.
Another method of treating esophageal atresia involves positioning a pair of catheters, each catheter having a magnetic tip as disclosed in U.S. Pat. No. 7,282,057. The magnetic forces created by both magnets results in approximation of the esophageal sacs.
The above-described conventional methods of correcting esophageal atresia present several drawbacks. The use of an external electromagnet requires that the infant be placed in a specially constructed bed having a large annular electromagnet. In addition to the expense associated with providing such a bed, the electromagnet itself can significantly impact the ability of caregivers to nurture the infant. The use of an external electromagnet also requires a subsequent procedure to surgically join the esophageal sacs into a continuous lumen. Surgically joining the esophageal sacs requires great surgical skill, and can present significant operative and post-operative complications. For example, surgical joining can result in the misalignment of the esophagus, and consequently, difficulty swallowing. Additional complications include gastroesophageal reflux, which can lead to ulcers in the lower part of the esophagus.
Applying traction through surgically placed sutures also presents several drawbacks. The main drawback of using sutures is the need for a significant surgical procedure once the esophageal sacs are sufficiently lengthened by the traction. This procedure involves surgically joining the esophageal sacs, which can result in a number of the complications detailed above. Moreover, as the sutures draw the esophageal sacs together, the sutures frequently tear out of one or both of the sacs. This requires at least one, and often multiple additional surgeries to re-suture the esophageal sacs. Additionally, if the approximation of the esophageal sacs occurs too quickly, the esophageal tissue may not regenerate at the required rate or the passageway formed between the esophageal sacs may be irregular, potentially leading to blockage of the passageway.
Accordingly, in view of the drawbacks of current technology, there is a desire for a system and a method for approximating the esophageal sacs of an infant afflicted with esophageal atresia and forming an open passageway between the two esophageal sacs.